Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quais barramentos de entrada/saída estão associados à marca Core i3-21xxt?
 ###Tabelas: CREATE TABLE core_i3 (core_i3_id AUTO_INCREMENT PRIMARY KEY, Codename (main article) VARCHAR, Brand name (list) VARCHAR, Cores INT, L3 Cache VARCHAR, Socket VARCHAR, TDP VARCHAR, I/O Bus VARCHAR) CREATE TABLE loans_in (loans_in_id AUTO_INCREMENT PRIMARY KEY, No. INT, P VARCHAR, Name VARCHAR, Country VARCHAR, Age INT, Loan Club VARCHAR, Started VARCHAR, Ended VARCHAR, Start Source VARCHAR, End Source VARCHAR) CREATE TABLE composition_of_the_5th_seanad (composition_of_the_5th_seanad_id AUTO_INCREMENT PRIMARY KEY, Administrative Panel INT, Agricultural Panel INT, Cultural and Educational Panel INT, Industrial and Commercial Panel INT, Labour Panel INT, National University of Ireland INT, University of Dublin INT, Nominated by the Taoiseach INT, Total INT) CREATE TABLE 2009 (2009_id AUTO_INCREMENT PRIMARY KEY, Opposing Teams VARCHAR, Against INT, Date VARCHAR, Venue VARCHAR, Status VARCHAR) CREATE TABLE external_links (external_links_id AUTO_INCREMENT PRIMARY KEY, SNO INT, College code VARCHAR, Faculty name VARCHAR, Designation VARCHAR, Qualification VARCHAR, Department VARCHAR, Experience VARCHAR)  
SELECT I/O Bus FROM core_i3 WHERE Brand name (list) = Core i3-21xxT